title: Factors associated with palliative withdrawal of mechanical ventilation and time to death after withdrawal.
abstract: BACKGROUND
  In imminently dying patients, mechanical ventilation withdrawal is often a comfort measure and avoids prolonging the dying process.
  
  
  OBJECTIVE
  The aim of the study was to identify factors associated with palliative withdrawal of mechanical ventilation and time to death after extubation.
  
  
  METHODS
  Logistic regression models were used to identify factors associated with palliative withdrawal of mechanical ventilation. Cox proportional hazards models were used to determine factors associated with time to death after extubation. We retrospectively evaluated 322 patients who died on mechanical ventilation or after palliative ventilator withdrawal at a single tertiary care center.
  
  
  RESULTS
  Of the 322 ventilated deaths, 159 patients had palliative withdrawal of mechanical ventilation and 163 patients died on the ventilator. Clinical service was associated with palliative withdrawal of mechanical ventilation: Patients withdrawn from the ventilator were less likely to be on the surgery service and more likely to be on the neurology/neurosurgical service. The median time to death was 0.9 hours (range 0-165 hours). Fraction of inspired oxygen (FIO2) greater than 70% (hazard ratio [HR] 1.92, 95% confidence interval [CI ]1.24-2.99) and a requirement for vasopressors (HR 2.06, 95% CI 1.38-3.09) were associated with shorter time to death. Being on the neurology/neurosurgical service at the time of ventilator withdrawal was associated with a longer time to death (HR 0.60, 95% CI 0.39-0.92).
  
  
  CONCLUSIONS
  Palliative withdrawal of mechanical ventilation was performed in only half of dying mechanically ventilated patients. Because clinical service rather than physiologic parameters are associated with withdrawal, targeted interventions may improve withdrawal decisions. Considering FIO2 and vasopressor requirements may facilitate counseling families about anticipated time to death.
authors.affiliation: 1 Department of Medicine, Division of Pulmonary and Critical Care Medicine, University of California , Los Angeles.
authors.forename: Thanh N
authors.initials: TN
authors.lastname: Huynh
authors.forename: Anne M
authors.initials: AM
authors.lastname: Walling
authors.forename: Thuy X
authors.initials: TX
authors.lastname: Le
authors.forename: Eric C
authors.initials: EC
authors.lastname: Kleerup
authors.forename: Honghu
authors.initials: H
authors.lastname: Liu
authors.forename: Neil S
authors.initials: NS
authors.lastname: Wenger
mesh_terms: D000368:Aged; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D010166:Palliative Care; D012121:Respiration, Artificial; D012189:Retrospective Studies; D012307:Risk Factors; D013727:Terminal Care; D063128:Tertiary Health Care; D013997:Time Factors; D028761:Withholding Treatment